<?php

// +----------------------------------------------------------------------
// | TOPThink [ WE CAN DO IT JUST THINK ]
// +----------------------------------------------------------------------
// | Copyright (c) 2010 http://topthink.com All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: 麦当苗儿 <zuojiazi.cn@gmail.com> <http://www.zjzit.cn>
// +----------------------------------------------------------------------
// | GIF.class.php 2013-03-09
// +----------------------------------------------------------------------

namespace application\extensions\ThinkImage\Driver;

class GIF {

    /**
     * GIF帧列表
     * @var array
     */
    private $frames = array();

    /**
     * 每帧等待时间列表
     * @var array
     */
    private $delays = array();

    /**
     * 构造方法，用于解码GIF图片
     * @param string $src GIF图片数据
     * @param string $mod 图片数据类型
     */
    public function __construct( $src = null, $mod = 'url' ) {
        if ( !is_null( $src ) ) {
            if ( 'url' == $mod && is_file( $src ) ) {
                $src = file_get_contents( $src );
            }

            /* 解码GIF图片 */
            try {
                $de = new GIFDecoder( $src );
                $this->frames = $de->GIFGetFrames();
                $this->delays = $de->GIFGetDelays();
            } catch (Exception $e) {
                throw new Exception( "解码GIF图片出错" );
            }
        }
    }

    /**
     * 设置或获取当前帧的数据
     * @param  string $stream 二进制数据流
     * @return boolean        获取到的数据
     */
    public function image( $stream = null ) {
        if ( is_null( $stream ) ) {
            $current = current( $this->frames );
            return false === $current ? reset( $this->frames ) : $current;
        } else {
            $this->frames[key( $this->frames )] = $stream;
        }
    }

    /**
     * 将当前帧移动到下一帧
     * @return string 当前帧数据
     */
    public function nextImage() {
        return next( $this->frames );
    }

    /**
     * 保存当前GIF图片
     * @param  string $gifname 图片名称
     */
    public function save( $gifname ) {
        $gif = new GIFEncoder( $this->frames, $this->delays, 0, 2, 0, 0, 0, 'bin' );
        file_put_contents( $gifname, $gif->GetAnimation() );
    }

}

/*
  :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
  ::
  ::	GIFEncoder Version 2.0 by László Zsidi, http://gifs.hu
  ::
  ::	This class is a rewritten 'GifMerge.class.php' version.
  ::
  ::  Modification:
  ::   - Simplified and easy code,
  ::   - Ultra fast encoding,
  ::   - Built-in errors,
  ::   - Stable working
  ::
  ::
  ::	Updated at 2007. 02. 13. '00.05.AM'
  ::
  ::
  ::
  ::  Try on-line GIFBuilder Form demo based on GIFEncoder.
  ::
  ::  http://gifs.hu/phpclasses/demos/GifBuilder/
  ::
  :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
 */

Class GIFEncoder {

    private $GIF = "GIF89a";  /* GIF header 6 bytes	 */
    private $VER = "GIFEncoder V2.05"; /* Encoder version		 */
    private $BUF = array();
    private $LOP = 0;
    private $DIS = 2;
    private $COL = -1;
    private $IMG = -1;
    private $ERR = array(
        'ERR00' => "Does not supported function for only one image!",
        'ERR01' => "Source is not a GIF image!",
        'ERR02' => "Unintelligible flag ",
        'ERR03' => "Does not make animation from animated GIF source",
    );

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFEncoder...
      ::
     */

    public function __construct(
    $GIF_src, $GIF_dly, $GIF_lop, $GIF_dis, $GIF_red, $GIF_grn, $GIF_blu, $GIF_mod
    ) {
        if ( !is_array( $GIF_src ) && !is_array( $GIF_tim ) ) {
            printf( "%s: %s", $this->VER, $this->ERR ['ERR00'] );
            exit( 0 );
        }
        $this->LOP = ( $GIF_lop > -1 ) ? $GIF_lop : 0;
        $this->DIS = ( $GIF_dis > -1 ) ? ( ( $GIF_dis < 3 ) ? $GIF_dis : 3 ) : 2;
        $this->COL = ( $GIF_red > -1 && $GIF_grn > -1 && $GIF_blu > -1 ) ?
                ( $GIF_red | ( $GIF_grn << 8 ) | ( $GIF_blu << 16 ) ) : -1;

        for ( $i = 0; $i < count( $GIF_src ); $i++ ) {
            if ( strToLower( $GIF_mod ) == "url" ) {
                $this->BUF [] = fread( fopen( $GIF_src [$i], "rb" ), filesize( $GIF_src [$i] ) );
            } else if ( strToLower( $GIF_mod ) == "bin" ) {
                $this->BUF [] = $GIF_src [$i];
            } else {
                printf( "%s: %s ( %s )!", $this->VER, $this->ERR ['ERR02'], $GIF_mod );
                exit( 0 );
            }
            if ( substr( $this->BUF [$i], 0, 6 ) != "GIF87a" && substr( $this->BUF [$i], 0, 6 ) != "GIF89a" ) {
                printf( "%s: %d %s", $this->VER, $i, $this->ERR ['ERR01'] );
                exit( 0 );
            }
            for ( $j = ( 13 + 3 * ( 2 << ( ord( $this->BUF [$i] { 10 } ) & 0x07 ) ) ), $k = TRUE; $k; $j++ ) {
                switch ( $this->BUF [$i] { $j } ) {
                    case "!":
                        if ( ( substr( $this->BUF [$i], ( $j + 3 ), 8 ) ) == "NETSCAPE" ) {
                            printf( "%s: %s ( %s source )!", $this->VER, $this->ERR ['ERR03'], ( $i + 1 ) );
                            exit( 0 );
                        }
                        break;
                    case ";":
                        $k = FALSE;
                        break;
                }
            }
        }
        GIFEncoder::GIFAddHeader();
        for ( $i = 0; $i < count( $this->BUF ); $i++ ) {
            GIFEncoder::GIFAddFrames( $i, $GIF_dly [$i] );
        }
        GIFEncoder::GIFAddFooter();
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFAddHeader...
      ::
     */

    private function GIFAddHeader() {
        $cmap = 0;

        if ( ord( $this->BUF [0] { 10 } ) & 0x80 ) {
            $cmap = 3 * ( 2 << ( ord( $this->BUF [0] { 10 } ) & 0x07 ) );

            $this->GIF .= substr( $this->BUF [0], 6, 7 );
            $this->GIF .= substr( $this->BUF [0], 13, $cmap );
            $this->GIF .= "!\377\13NETSCAPE2.0\3\1" . GIFEncoder::GIFWord( $this->LOP ) . "\0";
        }
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFAddFrames...
      ::
     */

    private function GIFAddFrames( $i, $d ) {

        $Locals_str = 13 + 3 * ( 2 << ( ord( $this->BUF [$i] { 10 } ) & 0x07 ) );

        $Locals_end = strlen( $this->BUF [$i] ) - $Locals_str - 1;
        $Locals_tmp = substr( $this->BUF [$i], $Locals_str, $Locals_end );

        $Global_len = 2 << ( ord( $this->BUF [0] { 10 } ) & 0x07 );
        $Locals_len = 2 << ( ord( $this->BUF [$i] { 10 } ) & 0x07 );

        $Global_rgb = substr( $this->BUF [0], 13, 3 * ( 2 << ( ord( $this->BUF [0] { 10 } ) & 0x07 ) ) );
        $Locals_rgb = substr( $this->BUF [$i], 13, 3 * ( 2 << ( ord( $this->BUF [$i] { 10 } ) & 0x07 ) ) );

        $Locals_ext = "!\xF9\x04" . chr( ( $this->DIS << 2 ) + 0 ) .
                chr( ( $d >> 0 ) & 0xFF ) . chr( ( $d >> 8 ) & 0xFF ) . "\x0\x0";

        if ( $this->COL > -1 && ord( $this->BUF [$i] { 10 } ) & 0x80 ) {
            for ( $j = 0; $j < ( 2 << ( ord( $this->BUF [$i] { 10 } ) & 0x07 ) ); $j++ ) {
                if (
                        ord( $Locals_rgb { 3 * $j + 0 } ) == ( ( $this->COL >> 16 ) & 0xFF ) &&
                        ord( $Locals_rgb { 3 * $j + 1 } ) == ( ( $this->COL >> 8 ) & 0xFF ) &&
                        ord( $Locals_rgb { 3 * $j + 2 } ) == ( ( $this->COL >> 0 ) & 0xFF )
                ) {
                    $Locals_ext = "!\xF9\x04" . chr( ( $this->DIS << 2 ) + 1 ) .
                            chr( ( $d >> 0 ) & 0xFF ) . chr( ( $d >> 8 ) & 0xFF ) . chr( $j ) . "\x0";
                    break;
                }
            }
        }
        switch ( $Locals_tmp { 0 } ) {
            case "!":
                $Locals_img = substr( $Locals_tmp, 8, 10 );
                $Locals_tmp = substr( $Locals_tmp, 18, strlen( $Locals_tmp ) - 18 );
                break;
            case ",":
                $Locals_img = substr( $Locals_tmp, 0, 10 );
                $Locals_tmp = substr( $Locals_tmp, 10, strlen( $Locals_tmp ) - 10 );
                break;
        }
        if ( ord( $this->BUF [$i] { 10 } ) & 0x80 && $this->IMG > -1 ) {
            if ( $Global_len == $Locals_len ) {
                if ( GIFEncoder::GIFBlockCompare( $Global_rgb, $Locals_rgb, $Global_len ) ) {
                    $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp );
                } else {
                    $byte = ord( $Locals_img { 9 } );
                    $byte |= 0x80;
                    $byte &= 0xF8;
                    $byte |= ( ord( $this->BUF [0] { 10 } ) & 0x07 );
                    $Locals_img { 9 } = chr( $byte );
                    $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp );
                }
            } else {
                $byte = ord( $Locals_img { 9 } );
                $byte |= 0x80;
                $byte &= 0xF8;
                $byte |= ( ord( $this->BUF [$i] { 10 } ) & 0x07 );
                $Locals_img { 9 } = chr( $byte );
                $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_rgb . $Locals_tmp );
            }
        } else {
            $this->GIF .= ( $Locals_ext . $Locals_img . $Locals_tmp );
        }
        $this->IMG = 1;
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFAddFooter...
      ::
     */

    private function GIFAddFooter() {
        $this->GIF .= ";";
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFBlockCompare...
      ::
     */

    private function GIFBlockCompare( $GlobalBlock, $LocalBlock, $Len ) {

        for ( $i = 0; $i < $Len; $i++ ) {
            if (
                    $GlobalBlock { 3 * $i + 0 } != $LocalBlock { 3 * $i + 0 } ||
                    $GlobalBlock { 3 * $i + 1 } != $LocalBlock { 3 * $i + 1 } ||
                    $GlobalBlock { 3 * $i + 2 } != $LocalBlock { 3 * $i + 2 }
            ) {
                return ( 0 );
            }
        }

        return ( 1 );
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFWord...
      ::
     */

    private function GIFWord( $int ) {

        return ( chr( $int & 0xFF ) . chr( ( $int >> 8 ) & 0xFF ) );
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GetAnimation...
      ::
     */

    public function GetAnimation() {
        return ( $this->GIF );
    }

}

/*
  :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
  ::
  ::	GIFDecoder Version 2.0 by László Zsidi, http://gifs.hu
  ::
  ::	Created at 2007. 02. 01. '07.47.AM'
  ::
  ::
  ::
  ::
  ::  Try on-line GIFBuilder Form demo based on GIFDecoder.
  ::
  ::  http://gifs.hu/phpclasses/demos/GifBuilder/
  ::
  :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
 */

Class GIFDecoder {

    private $GIF_buffer = array();
    private $GIF_arrays = array();
    private $GIF_delays = array();
    private $GIF_stream = "";
    private $GIF_string = "";
    private $GIF_bfseek = 0;
    private $GIF_screen = array();
    private $GIF_global = array();
    private $GIF_sorted;
    private $GIF_colorS;
    private $GIF_colorC;
    private $GIF_colorF;

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFDecoder ( $GIF_pointer )
      ::
     */

    public function __construct( $GIF_pointer ) {
        $this->GIF_stream = $GIF_pointer;

        $this->GIFGetByte( 6 ); // GIF89a
        $this->GIFGetByte( 7 ); // Logical Screen Descriptor

        $this->GIF_screen = $this->GIF_buffer;
        $this->GIF_colorF = $this->GIF_buffer [4] & 0x80 ? 1 : 0;
        $this->GIF_sorted = $this->GIF_buffer [4] & 0x08 ? 1 : 0;
        $this->GIF_colorC = $this->GIF_buffer [4] & 0x07;
        $this->GIF_colorS = 2 << $this->GIF_colorC;

        if ( $this->GIF_colorF == 1 ) {
            $this->GIFGetByte( 3 * $this->GIF_colorS );
            $this->GIF_global = $this->GIF_buffer;
        }
        /*
         *
         *  05.06.2007.
         *  Made a little modification
         *
         *
          -	for ( $cycle = 1; $cycle; ) {
          +		if ( $this->GIFGetByte ( 1 ) ) {
          -			switch ( $this->GIF_buffer [ 0 ] ) {
          -				case 0x21:
          -					$this->GIFReadExtensions ( );
          -					break;
          -				case 0x2C:
          -					$this->GIFReadDescriptor ( );
          -					break;
          -				case 0x3B:
          -					$cycle = 0;
          -					break;
          -		  	}
          -		}
          +		else {
          +			$cycle = 0;
          +		}
          -	}
         */
        for ( $cycle = 1; $cycle; ) {
            if ( $this->GIFGetByte( 1 ) ) {
                switch ( $this->GIF_buffer [0] ) {
                    case 0x21:
                        $this->GIFReadExtensions();
                        break;
                    case 0x2C:
                        $this->GIFReadDescriptor();
                        break;
                    case 0x3B:
                        $cycle = 0;
                        break;
                }
            } else {
                $cycle = 0;
            }
        }
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFReadExtension ( )
      ::
     */

    private function GIFReadExtensions() {
        $this->GIFGetByte( 1 );
        for (;; ) {
            $this->GIFGetByte( 1 );
            if ( ( $u = $this->GIF_buffer [0] ) == 0x00 ) {
                break;
            }
            $this->GIFGetByte( $u );
            /*
             * 07.05.2007.
             * Implemented a new line for a new function
             * to determine the originaly delays between
             * frames.
             *
             */
            if ( $u == 4 ) {
                $this->GIF_delays [] = ( $this->GIF_buffer [1] | $this->GIF_buffer [2] << 8 );
            }
        }
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFReadExtension ( )
      ::
     */

    private function GIFReadDescriptor() {
        $GIF_screen = array();

        $this->GIFGetByte( 9 );
        $GIF_screen = $this->GIF_buffer;
        $GIF_colorF = $this->GIF_buffer [8] & 0x80 ? 1 : 0;
        if ( $GIF_colorF ) {
            $GIF_code = $this->GIF_buffer [8] & 0x07;
            $GIF_sort = $this->GIF_buffer [8] & 0x20 ? 1 : 0;
        } else {
            $GIF_code = $this->GIF_colorC;
            $GIF_sort = $this->GIF_sorted;
        }
        $GIF_size = 2 << $GIF_code;
        $this->GIF_screen [4] &= 0x70;
        $this->GIF_screen [4] |= 0x80;
        $this->GIF_screen [4] |= $GIF_code;
        if ( $GIF_sort ) {
            $this->GIF_screen [4] |= 0x08;
        }
        $this->GIF_string = "GIF87a";
        $this->GIFPutByte( $this->GIF_screen );
        if ( $GIF_colorF == 1 ) {
            $this->GIFGetByte( 3 * $GIF_size );
            $this->GIFPutByte( $this->GIF_buffer );
        } else {
            $this->GIFPutByte( $this->GIF_global );
        }
        $this->GIF_string .= chr( 0x2C );
        $GIF_screen [8] &= 0x40;
        $this->GIFPutByte( $GIF_screen );
        $this->GIFGetByte( 1 );
        $this->GIFPutByte( $this->GIF_buffer );
        for (;; ) {
            $this->GIFGetByte( 1 );
            $this->GIFPutByte( $this->GIF_buffer );
            if ( ( $u = $this->GIF_buffer [0] ) == 0x00 ) {
                break;
            }
            $this->GIFGetByte( $u );
            $this->GIFPutByte( $this->GIF_buffer );
        }
        $this->GIF_string .= chr( 0x3B );
        /*
          Add frames into $GIF_stream array...
         */
        $this->GIF_arrays [] = $this->GIF_string;
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFGetByte ( $len )
      ::
     */

    /*
     *
     *  05.06.2007.
     *  Made a little modification
     *
     *
      -	public function GIFGetByte ( $len ) {
      -		$this->GIF_buffer = array ( );
      -
      -		for ( $i = 0; $i < $len; $i++ ) {
      +			if ( $this->GIF_bfseek > strlen ( $this->GIF_stream ) ) {
      +				return 0;
      +			}
      -			$this->GIF_buffer [ ] = ord ( $this->GIF_stream { $this->GIF_bfseek++ } );
      -		}
      +		return 1;
      -	}
     */

    private function GIFGetByte( $len ) {
        $this->GIF_buffer = array();

        for ( $i = 0; $i < $len; $i++ ) {
            if ( $this->GIF_bfseek > strlen( $this->GIF_stream ) ) {
                return 0;
            }
            $this->GIF_buffer [] = ord( $this->GIF_stream { $this->GIF_bfseek++} );
        }
        return 1;
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFPutByte ( $bytes )
      ::
     */

    private function GIFPutByte( $bytes ) {
        for ( $i = 0; $i < count( $bytes ); $i++ ) {
            $this->GIF_string .= chr( $bytes [$i] );
        }
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	PUBLIC FUNCTIONS
      ::
      ::
      ::	GIFGetFrames ( )
      ::
     */

    public function GIFGetFrames() {
        return ( $this->GIF_arrays );
    }

    /*
      :::::::::::::::::::::::::::::::::::::::::::::::::::
      ::
      ::	GIFGetDelays ( )
      ::
     */

    public function GIFGetDelays() {
        return ( $this->GIF_delays );
    }

}
